The present invention relates to a stent for positioning at a junction of a bifurcated blood vessel and the method of making such a stent. In the prior art, stents are well known and are commonly surgically implanted within blood vessels, whether arteries or veins, particularly at the conclusion of a surgical procedure known as a balloon angioplasty, which procedure is employed to flatten arterio-sclerosis induced deposits against the vessel wall, with the stent thereafter being implanted at the surgical site to deter and preclude narrowing of the flow passage through the blood vessel at the location where the stent is implanted.
It is well known to make a stent having a generally cylindrical tubular body shape having slots or other surface irregularities therethrough promoting adherence of the stent in the implanted location. It is also well known to make stents having end surfaces that are generally perpendicular to the axis of elongation of the stent body itself. Such stents are useful when implanted within blood vessels in areas not adjacent to a junction with another blood vessel or other type of bifurcation. Where implantation of a stent is required at an area of bifurcation of a blood vessel or other junction location therein, use of a stent having end surfaces perpendicular to the axis of elongation of the stent may be detrimental to the patient's recovery.
In this regard, when such a prior art stent is employed at a blood vessel junction or bifurcation, one "corner" of the stent may protrude into the adjacent blood vessel thereby interfering with smooth blood flow therethrough. Thus, while the stent is curing one problem in the blood vessel where it has been implanted, at the same time, it can be causing a new problem in the adjacent blood vessel by restricting flow, sometimes to a degree that might be analogous to the result of an advanced case of arterio-sclerosis.
Thus, a need has developed for a stent having a configuration facilitating implantation at a junction or bifurcation in a blood vessel so that the blood vessel where the stent is implanted is effectively treated while, at the same time, the adjacent or joining blood vessel suffers no ill effects as a result thereof. It is with this need in mind that the present invention was developed.